The United Nations (UN) has developed a system for the global control of narcotic drugs and psychotropic substances through a series of drug control Conventions.

The UN Single Convention on Narcotic Drugs, 1961,....as amended by the 1972 Protocol Amending the Single Convention on Narcotic Drugs (1961 Convention), the UN Convention on Psychotropic Substances, 1971 (1971 Convention) and the UN Convention against Illicit Traffic in Narcotic Drugs and Psychotropic Substances, 1988 (1988 Convention)...set out a system of controls relating to the international production and distribution of narcotic drugs and psychotropic substances.

Under the 1961Convention, parties have agreed to enact legislation that strictly controls the cultivation and distribution of opium poppy, coca and marihuana plants, and the production and distribution of other narcotics. All production, distribution and use of any substance listed under this convention must be limited to scientific or medical purposes.

Under the 1971Convention, psychoactive substances are to be subjected to controls similar to those that apply under the 1961 Convention. THC (delta-9-tetrahydrocannabinol) and other isolated marihuana derivatives, known as cannabinoids, are listed under this Convention.

Under the 1988 Convention, parties must cooperatively take action to control illicit cultivation, production and distribution of drugs of abuse. This includes the cultivation of marihuana."
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